I did IT Apps this year, and doing SD next year, and Software Development does seem to be a lot more challenging and more interesting.
About the IT Apps course:
U3O1 - Online Communites - you create a website (html, css etc.)
U3O2 - Databases
U4O1 - Spreadsheets OR databases
U4O2 - Security, relevant to IT legal stuff, ethics etc. - fairly straightforward theory
So yeah, it's pretty simple stuff - possibly things you're already familiar with (if not, they're straight forward to learn). To challenge myself, I tried to go beyond what was expected and set my own standards: stuff like going beyond the course when possible, producing a website that looks good, trying to stick to the text editor (I'm not a fan of Frontpage), playing around with javascript, read a bit more about database theory, try to find the most elegant solutions for a spreadsheet or a database etc. I think these doing these kinds of things made the subject a bit more interesting for me.
It's probably best to take your own judgement of what you think of spreadsheets and databases. However, compared to what is covered in SD, to me, it does seem quite dull in comparison.
From what I've looked at of the course content, Software Development always seems to go into a bit more technical depth than IT Applications when it comes to theory. About programming, I guess the only way to get better is to practice, practice and practice. If you ever get stuck, there's
plenty of resources for just about every programming language on the internet and for VB.net, there's plenty of books that have been written about it.
If you haven't already, to read about the courses in detail, take look at Mark Kelly's website
http://vceit.com/, and look at the lecture notes there.